Fix: variable names beginning with a keyword and dash

[groenroos]

What: Closes #2422

Why: Variable and mixin names that begin with a keyword (return, if, else, unless, for, or in), immediately followed by a dash (-), e.g. for-tablet, will trigger an error. They probably shouldn't.

How: Edited the regex of the keyword method in the lexer to ensure the keyword isn't directly followed by a -

Checklist:

• Documentation
• Unit Tests
• Code complete

[vendethiel]

I don’t think that [ \t]* does anything, does it? Only the 1st match group is skipped.

[groenroos]

I don’t think that [ \t]* does anything, does it? Only the 1st match group is skipped.

Removing it causes errors;

It seems like to me that the whitespace is indeed skipped as well, as it sends the entire captures array to skip;

stylus/lib/lexer.js

Lines 451 to 453 in 91b7701

	if (captures = /^(return|if|else|unless|for|in)\b(?!-)[ \t]*/.exec(this.str)) {
	var keyword = captures[1];
	this.skip(captures);

where skip uses the first value of the array (e.g. for , with trailing whitespace) to calculate the number of chars to skip:

stylus/lib/lexer.js

Lines 130 to 132 in 91b7701

	skip: function(len){
	var chunk = len[0];
	len = chunk ? chunk.length : len;

with the captures/len looking like this:

[
	'for ',
	'for',
	index: 0,
	input: 'for vendor in vendors\n' + ...,
	groups: undefined
]

[vendethiel]

where skip uses the first value of the array (e.g. for , with trailing whitespace)

Ah, if skip uses captures[0] then it makes sense

[iChenLei]

So that's why CI is important, it ensure our change be more controllable.